CN101665403B - Produce the improved method of 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb) - Google Patents

Abstract

The present invention provides production 2-chloro-1,1,1, the improved method of 2-tetrafluoropropane (HCFC-244bb), by by chloro-for 2-3,3,3-trifluoro propene (HCFO-1233xf) and fluohydric acid gas, react under the existence of hydrogen chloride and liquid-phase fluorination catalyst with liquid reactive form. Described hydrogen chloride joins this reaction from external source under about 100psig or higher pressure. Described HCFC-244bb is the intermediate of production 2,3,3,3-tetrafluoropropene-1 (HFO-1234yf).

Description

Produce the improved method of 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb)

The cross reference of related application

This application claims U. S. application number is 61/087206, and in the rights and interests of the temporary patent application that on August 8th, 2008 submits to, it is incorporated herein by.

Technical field

The present invention relates to for producing 2-chloro-1,1,1, the improved method of 2-tetrafluoropropane (HCFC-244bb), relate more specifically to by by chloro-for 2-3,3,3-trifluoro propane (HCFO-1233xf) and fluohydric acid gas, under the existence of hydrogen chloride and liquid-phase fluorination catalyst in liquid phase reactor container reaction and prepare the improved method of HCFC-244bb. Described HCFC-244bb is the intermediate preparing 2,3,3,3-tetrafluoropropenes (HFO-1234yf), and this 2,3,3,3-tetrafluoropropene is the cold-producing medium with low global warming trend.

Background technology

It is found in industrial tool in numerous applications based on the fluid of fluorocarbon to have been widely used, including cold-producing medium, aerosol propellant, foaming agent, heat-conduction medium and gaseous dielectric. Due to the suspected environmental problems relevant to the purposes of some this kind of fluid, including associated higher global warming trend, use and there is minimum possible greenhouse warm up the fluid of trend and zero ozone depletion trend and expected. Therefore in the material that exploitation is more friendly for the environment of above-mentioned application, has considerable interest. Tetrafluoropropene, has zero ozone depletion and low global warming trend, is identified as and is likely to meet these requirements. But, the toxicity of this kind of chemical substance, boiling point and other physical property are widely different between isomer. A kind of tetrafluoropropene with value characteristic is 2,3,3,3-tetrafluoropropenes (HFO-1234yf). HFO-1234yf is found to be effective cold-producing medium, heat-conduction medium, propellant, foaming agent, foaming agent, gaseous dielectric, germicide carriers, polymerisation medium, dedusting fluid, carrier fluid, polish agent, displacement drying agent and energy circulation working fluid. Accordingly, it would be desirable to the method for new production tetrafluoropropene especially 2,3,3,3-tetrafluoropropenes.

In US patent 2,931,840, chloromethanes and CF₂HCl obtains the CF containing about 15% 800 DEG C of pyrolysis together₃CF=CH₂Product stream. HFO-1234yf can also pass through CF₃CHFCH₂F and KOH together in butyl ether dehydrofluorination (Chem.Abstr.1961:349f) prepare, and pass through CF in US patent 4,900,874₃CF₂CH₂Prepared by the reaction of OH and hydrogen.

For preparation HFO-1234yf, continuous print also uses the method for the raw material that is easy to get to be advantageous for. Owing to art methods lacks one or more above-mentioned desired feature, it is therefore desirable to more favourable route, especially those are prone to mass-produced.

Producing at present in the method for HFO-1234yf, wherein a step needs HCFO-1233xf fluoride with fluohydric acid gas thus forming 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb). In the liquid-phase fluorination of HCFO-1233xf to prepare in HCFC-244bb, it does not have HCl generates, because this reaction is strict hydrofluorination reaction, wherein HF adds in double bond. With other production CFCs (such as CFC-12) known, HCFCs (such as HCFC-22, and HFCs (such as HFC-143a HCFC-142b), HFC-245fa) liquid phase fluorination reaction is compared, and the method that this HCl of not having side-product is formed is unique. This is because these reactions wholly or partly comprise halogen exchange. Namely F-replaces the Cl in molecule^-. That relatively increase, carry out liquid phase fluorination reaction under easy to reach pressure by the formation of HCl and be advantageous for. Because its right and wrong can be coagulated under desired reaction condition, the formation of HCl also enhances the mixing in reactor, and it easily can be discharged from the top of catalyst stripping equipment and by taking fluorinated product out of and helpful. Owing to not having the generation of HCl in the reaction from HCFO-1233xf to HCFC-244bb, the mixing in reactor is less, and this is likely to reduce conversion ratio and promote that by-product is formed. It addition, reactor is also more difficult to control because not having HCl to take, to form high pressure or help, the HCFC-244bb generated out of.

In the present invention, HCl and HF and HCFO-1233xf is combined together and is put in reactor. Reactor and catalyst stripping equipment picture routine produce above-mentioned CFCs, HCFC ' liquid phase fluorination reaction of s and HFCs equally operates. So there are many benefits. It makes reaction complete under the pressure relatively increased and carry out, and which increases the mixing in reactor, and it easily leaves reactor with product HCFC-244bb from the top of catalyst stripping equipment. Described HCl combines the substantially inertia of feeding intake, and cannot participate in fluorination reaction, and produces few or do not have undesirable by-product. The source of any HCl may be incorporated for this reaction. Preferably using the HCl in the generation of front step situ in the multistep reaction preparing HFO-1234yf as HCl source. The example of this step includes the fluorination reaction of 1,1,2,3-tetrafluoropropene or 1,1,1,2,3-pentachloropropane and HF, optional but preferably in the presence of a fluorination catalyst, form HCFO-1233xf intermediate and HCl. Then, the HCl that all of or only a part generates in this step is combined to be dosed in the liquid phase fluorination reactor preparing HCFC-244bb.

Summary of the invention

The present invention is provided to preparation 2-chloro-1,1, the method of 1,2-tetrafluoropropane, it includes chloro-for 2-3,3,3-trifluoro propene and fluohydric acid gas, in liquid phase reactor container, react under the existence of hydrogen chloride and liquid-phase fluorination catalyst, wherein, described hydrogen chloride joins this reaction from external source under about 100psig or higher pressure.

The present invention also provides for for preparing 2,3,3, the method of 3-tetrafluoropropene, it includes (i) by chloro-for 2-3,3,3-trifluoro propene and fluohydric acid gas, with liquid reactive form and combine the hydrogen chloride that feeds intake, react continuously under the existence of liquid-phase fluorination catalyst, 2-chloro-1 is comprised with preparation, the compositions of 1,1,2-tetrafluoropropane, wherein, described hydrogen chloride is joined in this reaction by external source under about 100psig or higher pressure; Then (ii) when effectively preparation 2,3,3,3-tetrafluoropropene by described 2-chloro-1,1,1,2-tetrafluoropropane dehydrohalogenation.

The present invention also provides for the method for preparing 2,3,3,3-tetrafluoropropenes, comprising:

A) fluoride 1,1,2,3-tetrachloropropylene is to prepare 2-chloro-3,3,3 ,-trifluoropropene;

B) by chloro-for 2-3,3,3-trifluoro propene and fluohydric acid gas, with liquid reactive form and combine the hydrogen chloride that feeds intake, react under the existence of liquid-phase fluorination catalyst, 2-chloro-1 is comprised with preparation, the compositions of 1,1,2-tetrafluoropropane, wherein, described hydrogen chloride under about 100psig or higher pressure by external source in joining this reaction; Then

C) when effectively preparation 2,3,3,3-tetrafluoropropene by described 2-chloro-1,1,1,2-tetrafluoropropane dehydrohalogenation.

Detailed description of the invention

For preparing 2-chloro-1,1,1, the first step in the method for 2-tetrafluoropropane (HCFC-244bb) needs chloro-for 2-3,3,3-trifluoro propene (HCFO-1233xf) and fluohydric acid gas, react under the existence of hydrogen chloride and liquid-phase fluorination catalyst in liquid phase reactor container, thus prepare HCFC-244bb. Preferably this reaction carries out continuously.

HCFO-1233xf is the intermediate in the preparation of 2,3,3, the 3-tetrafluoropropenes (HFO-1234yf) as described in US patent application 20070007488 and 20070197842 known in prior art, and their description is incorporated herein by. In the method preparing HCFO-1233xf, precursor agents and fluohydric acid gas generation fluorination reaction. This reaction can pass through such as CCl₂=CClCH₂Gas phase or the liquid phase catalytic fluorination of Cl and HF obtain HCFO-1233xf and realize. The product of this kind of precursor includes HCFO-1233xf, unreacted HF, HCl, and other is separated into the by-product of component subsequently.

In the practical operation of the present invention, liquid-phase catalyst described below was filled in fluorination reactor before reacting by heating device. The reactor of any applicable fluorination reaction may be used to the present invention. Preferred described reactor builds the material of the corrosiveness from hf resi stant, for instance Hastelloy-C, Inconel, the container of monel metal (Monel) and fluoropolymer-lined. These liquid phase fluorination reactor are known in the prior art. Then after reactor reaches desired temperature, HF, HCl and HCFO-1233xf are dosed in reactor. In preferred embodiments, reaction is at about 30 DEG C to about 200 DEG C, more preferably in about 50 DEG C to about 150 DEG C, and more preferably from about carries out at the temperature of 75 DEG C to about 125 DEG C further. The pressure of this reaction along with temperature, hydrogen chloride and hydrofluoric consumption, and the conversion ratio of HCFO-1233xf and change. The operation pressure being suitable for be about 5psia to about 200psia, and preferably 30 to about 175psia, and most preferably from about 60psia extremely about 150psia.

In preferred embodiments, the consumption of catalyst is about 2% to about 80% based on the molar percentage of HCFO-1233xf, and preferably about 5% to about 50%, and most preferably from about 10% to about 20%. Fluorination catalyst preferably has the purity of at least 98%.

Measuring based on reactive chemistry, the mol ratio of required HF and HCFO-1233xf is at least equal to the quantity of double bond in initial Organic Ingredients, and preferably excessive. In preferred embodiments, the mol ratio of described HF and HCFO-1233xf is at least about 1: 1 to about 50: 1, more preferably about 1: 1 to about 30: 1, and and most preferably about 2: 1 to about 15: 1. In HF, arbitrary water all will with catalyst reaction also so as to inactivate. It is preferred to substantially anhydrous HF. Described " substantially anhydrous " means contain the water less than about 0.05 weight % in this HF and preferably comprise the water less than about 0.02 weight %. But, one skilled in the art will recognize that the water existed in catalyst can be compensated by by the consumption of increase catalyst. HF suitable in this reaction can obtain from the HoneywellInternationalInc. of Morristown, N.J.

Liquid phase fluorination reaction carries out increasing the pressure of reactor under the existence of enough hydrogen chloride, obtains higher pressure compared with the similar liquid phase reactor being not added with hydrogen chloride. In preferred embodiments, the mol ratio of HCl and HCFO-1233xf is about 0.1: 1 to about 10: 1, more preferably about 1: 1 to about 5: 1 and and most preferably about 1: 1 to about 3: 1. Described hydrogen chloride joins in this reaction from external source under about 100psig or higher pressure; It is preferably from about 100psig to about 500psig, more preferably about 120psig to about 300psig.

Any liquid phase fluorination reaction catalyst can be used for the present invention. Non exhaustive examples includes lewis acid, transition metal halide, transition metal oxide, IVb race metal halide, Vb race metal halide, or their combination. The non-exclusive example of liquid-phase fluorination catalyst is antimony halides, tin halides, halogenation tantalum, halogenated titanium, halogenation niobium and halogenation molybdenum, iron halide, fluoride hafnium halide, fluorinated chromium or their combination. The concrete non-exclusive example of liquid-phase fluorination catalyst is SbCl₅, SbCl₃, SbF₅, SnCl₄, TaCl₅, TiCl₄, NbCl₅, MoCl₆, FeCl₃, CrF₃, Cr₂O₃, SbCl₅Fluoride, SbCl₃Fluoride, SnCl₄Fluoride, TaCl₅Fluoride, TiCl₄Fluoride, NbCl₅Fluoride, MoCl₆Fluoride, FeCl₃Fluoride, Cr₂O₃Fluoride, or their combination. Liquid-phase fluorination catalyst includes SbCl₅, SbCl₃, SbF₅, SnCl₄, TaCl₅, TiCl₄, NbCl₅, MoCl₆, FeCl₃, CrF₃, Cr₂O₃, SbCl₅Fluoride, SbCl₃Fluoride, SnCl₄Fluoride, TaCl₅Fluoride, TiCl₄Fluoride, NbCl₅Fluoride, MoCl₆Fluoride, FeCl₃Fluoride, Cr₂O₃Fluoride, or their combination.

If these catalyst become inactivation, then they easily can be regenerated by any methods known in the art. A kind of method of suitable regeneration catalyzing agent includes logical cl gas flow in catalyst. Such as, for every pound of liquid-phase fluorination catalyst, the chlorine of about 0.002 to about 0.2lb can be added per hour in liquid phase reactor. This can pass through such as at the temperature of about 65 DEG C to about 100 DEG C, continues about 1 to about 2 hour or carries out continuously.

The HCFC-244bb of gained, and HF and HCl can by any isolated or purified method well known in the prior art, for instance neutralize and distillation, reclaim from reactant mixture. This HCFC-244bb in a pure form, or optionally can be used as the intermediate of preparation 2,3,3,3-tetrafluoropropene HFO-1234yf with partial-purified form or impure form with the whole effluents obtained from HCFC-244bb production stage. The method of the present invention can be implemented in mode in batches or continuously. In a continuous process, described HCFO-1233xf, HCl and HF are dosed in reactor after reaching preferred temperature preferably in reactor simultaneously. The temperature and pressure of fluorination reaction all keeps essentially identical in batch mode and continuation mode. The time of staying or time of contact are about 1 second to about 2 hours, it is preferable that about 5 seconds to about 1 hour, and most preferably from about 10 seconds to about 30 minutes. Must there is enough catalyst to complete fluorination reaction within the above-mentioned time of staying. In continuous operation mode, HF, HCFC-244bb and hydrogen chloride are removed continuously from reactor.

In preferred embodiments, the present invention relates to multistep method, wherein, before the above-mentioned method preparing HCFC-244bb immediately one by 1,1,2,3-tetrachloropropylene (HCC-1230xa) or 1,1,1,2,3-tetra-chloropropanes (HCC-240db) and hydrofluoric gas phase fluorination prepare 2-chloro-3,3,3-trifluoro propene (HCFO-1233xf) comprise fluohydric acid gas at first processing step to generate, the stream of 2-chloro-3,3,3 ,-trifluoropropene and hydrogen chloride. Preferably all, directly it is dosed in the liquid phase reactor preparing HCFC-244bb more preferably at the part of this stream.

This reaction can carry out in being arbitrarily suitable to the reactor of gas phase or liquid phase fluorination reaction. Preferred reactor builds the material from anti-fluohydric acid gas and the corrosiveness of catalyst, for instance Hastelloy-C, Inconel, the container of monel metal (Monel) and fluoropolymer-lined. In gas phase process, reactor is filled catalysts for gas phase fluorination. Any fluorination catalyst well known in the prior art may be used to this technique. Suitable catalyst includes, but are not limited to the oxide of chromium, aluminum, cobalt, manganese, nickel and ferrum, hydroxide, halogenide, oxyhalide, its inorganic salt and their mixture. The combination of the catalyst of the suitable present invention is non-exclusive includes Cr₂O₃, Cr₂O₃/Al₂O₃, Cr₂O₃/AlF₃, Cr₂O₃/ carbon, CoCl₂/Cr₂O₃/Al₂O₃, NiCl₂/Cr₂O₃/Al₂O₃, CoCl₂/AlF₃, NiCl₂/AlF₃Mixture with them. Chromium oxide/aluminum oxide catalyst has description in US patent No.5,155,082, and it is incorporated herein by. Preferred chromium (III) oxide such as crystal chromium oxide or amorphous chromium, it is most preferred that amorphous chromium. Chromium oxide (Cr₂O₃) it is the commercially available material can buied with multiple granularity. Fluorination catalyst preferably has the purity of at least 98%. It is excessive that described fluorination catalyst exists for, but is at least the amount being enough to drive reaction to carry out.

Reactor is pre-heated to fluorination reaction temperature, anhydrous HF is dosed to reactor simultaneously. 1,1,2,3-tetrachloropropylene (HCC-1230xa) or 1,1,1,2,3-tetra-chloropropane (HCC-240db) and HF can add reactor under what convenient temperature and pressure in office. In preferred embodiments, before being dosed in reactor, any one or the both of which pre-vaporized of HCC-1230xa or HCC-240db and HF or be preheated to the temperature of about 30 DEG C to about 300 DEG C. In another embodiment, HCC-1230xa or HCC-240db and HF gasifies in the reactor. Then the inventory of HF and HCC-1230xa or HCC-240db adjusts desired mol ratio. The mol ratio of HF and HCC-1230xa or HCC-240db is preferably from about 3: 1 to about 100: 1; Even more preferably about 4: 1 to about 50: 1 and and most preferably about 5: 1 to about 20: 1.

Gas phase fluorination is at preferably about 80 DEG C to about 400 DEG C; More preferably from about carry out at the temperature of 100 DEG C to about 350 DEG C and most preferably from about 200 DEG C to about 330 DEG C. The pressure of reactor is not critical and can be super-atmospheric pressure, atmospheric pressure or vacuum. Vacuum pressure can be about 5 holders (.0966psig) and holds in the palm (14.69psig) to about 760. In gas phase fluorination, HCC-1230xa or HCC-240db and HF carries out in the presence of a fluorination catalyst in the gas phase. Reactant gas can contact about 1-120 second or more preferably from about 1-20 second with fluorination catalyst. In order to reach the purpose of the present invention, " time of contact " assumes that, when catalyst bed is 100% sky, gas reactant passes through the time required for catalyst bed.

In preferred embodiments, process flow passes downwardly through catalyst bed. Before every use, the preferred drying of catalyst, preprocessed and activated. Regularly catalyst regeneration can also be advantageous for after being placed in the medium-term and long-term use of reactor. Pretreatment can be realized to about 430 DEG C by heatable catalyst in nitrogen stream or other inert gas flow to about 250 DEG C. Then described catalyst can by activating to obtain high catalyst activity with by the HF stream process of large excess of nitrogen dilution by it. The regeneration of catalyst such as can be used such as O by the means that any prior art is known₂Or the oxidant of chlorine realizes. Such as, by air or with the air of nitrogen dilution at about 100 DEG C to about 400 DEG C, it is preferable that by catalyst at the temperature of about 200 DEG C to about 375 DEG C, the size according to reactor, continue about 8 hours to about 3 days.

In one embodiment, HCFO-1233xf from comprising unreacted starting material, can pass through any any means known in this area, for instance reclaim by distilling in the fluorination reaction product mixtures of the by-product containing HCl, HF and HCFO-1233xf. Such as, described distillation can preferably in standard distillation column lower than about 300psig, it is preferable that carry out lower than about 200psig with under being most preferably less than the pressure of 150psig. The pressure of this distillation column determines distillation procedure temperature inherently. HCl can pass through at about-40 DEG C to about 25 DEG C, it is preferable that operates distillation column at about-40 DEG C to about-20 DEG C and reclaims. HCFO-1233xf can be reclaimed by operation distillation column at about-10 DEG C to about 60 DEG C. Single or multiple distillation column can be used. Distillate part and comprise essentially all of HCl and HCFO-1233xf (obtaining in reaction), and base section comprises HF and other impurity.

But, in a more preferred embodiment, the product stream comprising HCFO-1233xf, HCl and HF from this step is directly dosed in above-mentioned liquid phase reactor from gas phase fluorination, and HCFO-1233xf is converted into HCFC-244bb by it.

In another embodiment, the HCFC-244bb of the generation then dehydrohalogenation when effectively preparation 2,3,3,3-tetrafluoropropenes (HFO-1234yf). Preferably this dehydrohalogentaion step includes gas or gas phase catalytic reaction.

The catalyzed conversion of HCFC-244bb effectively by HCFC-244bb dehydrochlorination to prepare 2,3,3,3-tetrafluoropropenes (HFO-1234yf) when carry out. The dehydrochlorination of preferred HCFC-244bb, in gas phase, carries out in the gas phase more preferably in fixed bed reactors. Described de-hydrogen halide can carry out in the reaction vessel of any appropriate or reactor, but it should preferably build the material (degree is this material be dehydrohalogenation when formed) from the corrosiveness with anti-hydrogen chloride, such as nickel and its alloy, including Hastelloy, the container of Inconel, Incoloy and monel metal (Monel) or fluoropolymer-lined also can use one or more pipeline equipped with dehydrohalogenation catalyst.

The catalyst of HFO-1234yf is prepared for HCFC-244bb dehydrochlorination

Catalyst can be in bulk or supported form metal halide, through the metal-oxide of halogenation, and neutral (or zero oxidation state) metal or metal alloy, or activated carbon. When using metal halide or during metal oxide catalyst, it is preferable that one, two and tri-valent metal halides, oxide or their mixtures/combinations, and more preferably one, and bivalent metal halide and their mixtures/combinations. Composition metal includes, but are not limited to Cr³⁺, Fe³⁺, Mg²⁺, Ca²⁺, Ni²⁺, Zn²⁺, Pd²⁺, Li⁺, Na⁺, K⁺And Cs⁺. Composition halogen includes, but are not limited to F^-, Cl^-, Br^-And I^-. Useful one or bivalent metal halide example include, but are not limited to LiF, NaF, KF, CsF, MgF₂, CaF₂, LiCl, NaCl, KCl and CsCl. Halogenation treatment can include any method as known in the art, and especially those use HF, F₂, HCl, Cl₂, HBr, Br₂, HI and I₂Method as halogenation source.

When using neutrality, i.e. zeroth order, metal, when metal alloy and their mixture. Useful metal includes, but are not limited to Pd, Pt, Rh, Fe, Co, Ni, Cu, Mo, Cr, Mn and the above-mentioned combination as alloy or mixture. Catalyst can be support or unsupported. The example of useful metal alloy includes, but are not limited to SS316, Monel400, Inconel825, Inconel600, and Inconel625.

HCFC-244bb can in a pure form, partial-purified form or be directed in reactor as a part for the reactor effluent from preceding step. HCFC-244bb can optionally and such as nitrogen, and the inert gas diluent such as argon feeds intake together. In a preferred embodiment of the invention, HCFC-244bb is before entering the reactor by pre-vaporized or preheating. Alternatively, HCFC-244bb can gasify in reactor. Available reaction temperature can be about 100 DEG C to about 700 DEG C. Preferred temperature can be about 150 DEG C to about 600 DEG C, and preferred temperature can be about 200 DEG C to about 550 DEG C. This reaction at atmospheric pressure, can carry out under super-atmospheric pressure or vacuum condition. Vacuum pressure can be about 5 holders (.0966psig) and holds in the palm (14.69psig) to about 760. Can be about the time of contact of HCFC-244bb and catalyst 0.5 second to about 120 seconds, but be used as the longer or shorter time.

In the embodiment of the dehydrofluorination described in this section preferably, the conversion ratio of HCFC-244bb is at least about 10%, and more preferably at least about 20%, and even more preferably it is at least about 30%. Preferred in these embodiments, the selectivity of HFO-1234yf is at least about 70%, more preferably at least about 85% and more preferably at least about 95%.

In preferred embodiments, process flow passes through catalyst bed downward or upward. Regularly catalyst regeneration can also be advantageous for after long-term use in being placed in reactor. The regeneration of catalyst such as can be used such as O by any means known in the art₂Or the oxidant of chlorine realizes. Such as, by air or with the air of nitrogen dilution at about 100 DEG C to about 400 DEG C, it is preferable that by catalyst at the temperature of about 200 DEG C to about 375 DEG C, the size according to reactor, continue about 0.5 hour to about 3 days.

Generally speaking, the effluent of de-hydrogen halide step, including any middle effluent being likely to be present in during multistep reaction device is arranged, it can be processed and realize desired separating degree and/or other operation. Such as, comprising in the embodiment of HFO-1234yf at reactor effluent, described effluent generally also includes HCl and unreacted HCFC-244bb. Partially or substantially whole said components in product can such as be neutralized by any isolated or purified method known in the art and be distilled, and reclaim from reactant mixture. It is intended that unreacted HCFC-244bb can completely or partially circulate, to improve required CF₃CF=CH₂(HFO-1234yf) gross production rate. Optional but preferred hydrogen chloride reclaims after dehydrochlorination reaction. Reclaiming of hydrogen chloride is undertaken by conventional distillation, and wherein it removes from fraction.

Alternatively, HCl can by using water or caustic scrubber to reclaim or remove. When using water extractor, HCl is removed as aqueous solution. When a base is employed, HCl is only used as the aqueous solution of chlorate and removes from system.

In the optional embodiment of the present invention, the dehydrohalogenation of HCFC-244bb can also pass through it and include but not limited to KOH, NaOH, Ca (OH)₂React when high temperature with the strong base solution of CaO and realize. In this case, the concentration of aqueous slkali is about 2wt% to about 100wt%, more preferably from about 5wt% to about 90wt% and most preferably from about 10wt% to about 80wt%. The mol ratio of alkali and HCFC-244bb is preferably from about 1: 1 to about 2: 1; Even more preferably about 1.1: 1 to about 1.5: 1 and and most preferably about 1.2: 1 to about 1.4: 1. This reaction at about 20 DEG C to about 100 DEG C, more preferably from about can carry out at the temperature of 30 DEG C to 90 DEG C and most preferably from about 40 DEG C to about 80 DEG C. As above, this reaction at atmospheric pressure, can carry out under super-atmospheric pressure or vacuum. Vacuum pressure can be about 5 holders (.0966psig) and holds in the palm (14.69psig) to about 760. Furthermore it is possible to optionally employ solvent or phase transfer catalyst such as Aliquat336 to help Organic substance to be dissolved in alkaline solution. This optional step can use the solvent for described purpose well known in the art to carry out. Afterwards, HFO-1234yf can by any means known in the art from the mixture of reaction products comprising unreacted initiation material and by-product, for instance reclaimed by the method extracted and preferably distill. The mixture of HFO-1234yf and any by-product passes through distillation column. Such as, this distillation can carry out under atmospheric pressure, super-atmospheric pressure or vacuum condition preferably in standard distillation column. Preferred described pressure is lower than about 300psig, it is preferable that lower than about 200psig and be most preferably less than 150psig. The pressure of described distillation column determines distillation procedure temperature inherently. In these dehydrofluorination embodiments described in this section, it is preferable that the conversion ratio of HCFC-244bb is at least about 60%, more preferably at about 75%, with even more preferably from least about 90%. In these embodiments, it is preferable that the selectivity of HFO-1234yf is at least about 70%, more preferably at least about 85% and more preferably at least about 95%.

Following nonlimiting examples is used for describing the present invention in detail.

Embodiment 1

The Continuous Liquid Phase fluorination reaction of 2-chloro-3,3,3 ,-trifluoropropene (HCFO-1233xf)+HF �� 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb) is proved when HCl continuous dosing. The fluorination catalyst of this experiment is SbCl₅��

It is being equipped with catalyst stripping equipment, 2 inches of ID (internal diameter) packed columns and for returning the catalyst carried secretly, some unreacted HF and some unreacted HCFO-1233xf Teflon to the condenser in reactor in successive reaction mode when system is run^TMIn the Liquid-phase reactor of lining, the trade mark of E.I.duPontdeNemours&Co (Teflon be) is containing 6500 grams of SbCl₅. This reactor is 2.75 inches of ID �� 36 inch L (length) and unequipped blender/agitator. This reactor is heated to about 85 DEG C-87 DEG C. Then pass through 1500 grams of HF of addition and succeeded by 1500 grams of Cl₂Carry out activating catalytic agent. The pressure of response system is brought up to about 100psig by the HCl produced by the fluorination reaction of catalyst, is controlled in herein. It is first begin to continuous dosing gas HF. Being blasted in liquid catalyst by dip-tube with the speed of 1.1lb/hr, then when adding the HF of 1.0lbs, gas HCl and 2-chloro-3,3,3 ,-trifluoropropene start to feed intake. They also enter in liquid catalyst via dip-tube. HCl and HCFO-1233xf is respectively with the speed continuous dosing of 0.56lb/hr and 1.0lb/hr. The mol ratio of HF and 1233xf is 7.1: 1, and the mol ratio of HCl and 1233xf is 2: 1. Reaction temperature is maintained at 85 DEG C-87 DEG C and pressure is maintained at 100psig. HCl is gaseous state under these conditions and is inertia (that is, not reacting). Owing to it blasts liquid reaction mixture, because then it increases mixing tempestuously, and due to high vapour pressure thus it helps to maintain the pressure of reactor. It leaves response system by the top of catalyst stripping equipment and contributes to product, and HCFC-244bb therewith takes out of. This experiment runs 50 hours continuously. For this operation, the average conversion of HCFO-1233xf is > 99% and the selectivity of 244bb is reached 98%.

Embodiment 2

In embodiment 1 from catalyst stripping equipment top out mainly comprise HCFC-244bb, the stream of unreacted HF and HCl is dosed in the distillation column of routine, wherein HCl is recovered and/or is recycled back to Liquid-phase reactor to help mixing, keeps pressure and takes product out of.

Embodiment 3

2000 gallons of plant-scale reactors add antimony pentachloride catalyst. HCFO-1233xf and HF is by continuous dosing to reaction vessel. HF excessively feeds intake. Add hydrogen chloride as additional component to help mixing and to help the volatilization of product. HCFC-244bb, HF and hydrogen chloride leave described container and are recovered.

Embodiment 4

This embodiment illustrates the continuous gas phase fluorination of 1,1,2,3-tetrachloropropylene (TCP)+3HF �� 2-chloro-3,3,3 ,-trifluoropropene (HCFO-1233xf)+3HCl. For the Cr that the fluorination catalyst of this experiment is perfluorinated₂O₃��

Use by N2, HF and organic feeding system, feed intake carburator, superheater, 4 " the Monel reactor of ID, acid cleaning device, the continuous gas phase fluorination device system of exsiccator and product collection system composition studies this reaction. Reactor is loaded Cr 9415.2 grams preheated₂O₃Catalyst, it corresponds approximately to 6.5 liters of catalyst. Then, load after in constant temperature sand-bath at N at reactor₂Purge the reaction temperature that under catalyst, reactor is heated to about 235 DEG C. This reactor is under the pressure of about 3psig. HF feed intake as with N₂Feed intake altogether and be directed in reactor (by carburator and superheater) 15 minutes, now stop N₂Flowing. Then HF flowing velocity is regulated to 1.4lb/hr, then start 1,1,2, the 3-tetrachloropropylene (TCP) (through carburator and superheater) that feeds intake in reactor. The rate of feeding of TCP is steadily maintained at about 0.8lb/hr and HF rate of feeding and is steadily maintained at 1.4lb/hr so that mole material ratio of HF and TCP is for about 15: 1. Once reaction starts, the temperature of catalyst bed just rises to 250 DEG C-260 DEG C. At 250-260 DEG C, when 3psig and above-mentioned rate of feeding, time of contact is calculated as about 16 seconds. The HCFO-1233xf on average consisting of about 97.2GC area % of the material that production (on-stream) time more than 500 hours collects, the 244bb of 1.6GC area %, the HCFO-1231xf of HCFC-1223xd and the 0.08GC area % of HFO-1234yf/HFC-245cb, the 0.1GC area % of 0.6GC area %. When catalyst starts inactivation after 500 hours, because the selectivity of HCFO-1233xf is reduced so starting that chloro-3, the 3-difluoropropenes (HCFO-1232xf) of intermediate 2,3-bis-that fluoride is not enough occur. When the selectivity of HCFO-1233xf being dropped to about 83% after the production time when 650 is little, react due to the forfeiture of catalyst activity and stop. In whole operation process, the conversion ratio of TCP is maintained at > 99%.

Embodiment 5

The reactor effluent being obtained by reacting described in embodiment 4 is dosed to conventional distil-lation post, wherein reclaims HCl fraction. Mainly contain unreacted HF and HCFO-1233xf bottom distillation column and be put into and carry out extra process/purification. Then the HCl reclaimed is used as combining the source of the HCl that feeds intake whole or in part and puts in the liquid-phase reaction system described in embodiment 1.

After the present invention carrying out detail display with reference to preferred embodiment and describes, those skilled in the art are readily appreciated that and can make a variety of changes and improve when without departing from present subject matter and scope. Claims are intended to be construed to contain disclosed embodiment, the above-mentioned deformation discussed and their equivalents all.

Claims (15)

1. it is used for preparing 2-chloro-1,1,1, the method of 2-tetrafluoropropane, it includes 2-chloro-3,3,3 ,-trifluoropropene and fluohydric acid gas, reacting under the existence of hydrogen chloride and liquid-phase fluorination catalyst with liquid reactive form, wherein said hydrogen chloride joins this reaction from external source under about 100psig or higher pressure.

2. the process of claim 1 wherein, the mol ratio of the described hydrogen chloride and 2-chloro-3,3,3 ,-trifluoropropene that are dosed to reaction is at least 0.1: 1 to 10: 1.

3. the process of claim 1 wherein, described liquid-phase fluorination catalyst includes SbCl₅, SbCl₃, SbF₅, SnCl₄, TaCl₅, TiCl₄, NbCl₅, MoCl₆, FeCl₃, CrF₃, Cr₂O₃, SbCl₅Fluoride, SbCl₃Fluoride, SnCl₄Fluoride, TaCl₅Fluoride, TiCl₄Fluoride, NbCl₅Fluoride, MoCl₆Fluoride, FeCl₃Fluoride, Cr₂O₃Fluoride, or their combination.

4. the method for claim 1, farther includes to reclaim the step of described hydrogen chloride.

5. the process of claim 1 wherein, described 2-chloro-3,3,3 ,-trifluoropropene is prepared by the method that comprises fluoride 1,1,2,3-tetrachloropropylene.

6. the method for claim 5, wherein, described 1,1,2,3-tetrachloropropylene fluohydric acid gas fluoride is also thus obtained by reacting and comprises fluohydric acid gas, the intermediate stream of 2-chloro-3,3,3 ,-trifluoropropene and hydrogen chloride.

7. the method for claim 6, farther includes to reclaim the step of described hydrogen chloride.

8. the method for claim 7, wherein, at least some of HCl stream reclaimed directly is dosed in Liquid-phase reactor.

9. preparation 2,3,3, the method of 3-tetrafluoropropene, it includes (i) by chloro-for 2-3,3,3-trifluoro propene and fluohydric acid gas, with liquid reactive form and combine the hydrogen chloride that feeds intake, react continuously under the existence of liquid-phase fluorination catalyst, comprise 2-chloro-1 with preparation, 1, the compositions of 1,2-tetrafluoropropane, wherein said hydrogen chloride joins reaction from external source under about 100psig or higher pressure; Then (ii) when effectively preparation 2,3,3,3-tetrafluoropropene by described 2-chloro-1,1,1,2-tetrafluoropropane dehydrohalogenation.

10. the method for claim 9, wherein, described in comprise 2-chloro-1,1,1,2-tetrafluoropropane compositions comprise fluohydric acid gas and hydrogen chloride further.

11. the method for claim 9, wherein, described 2-chloro-3,3,3 ,-trifluoropropene is prepared by the method that comprises fluoride 1,1,2,3-tetrachloropropylene.

12. the method for claim 11, wherein, described 1,1,2,3-tetrachloropropylene fluohydric acid gas fluoride is also thus obtained by reacting and comprises fluohydric acid gas, the intermediate stream of 2-chloro-3,3,3 ,-trifluoropropene and hydrogen chloride.

13. the method for claim 12, farther include to reclaim the step of described hydrogen chloride.

14. the method for claim 13, wherein, at least some of HCl stream reclaimed directly is dosed in Liquid-phase reactor.

15. the method being used for preparing 2,3,3,3-tetrafluoropropenes, comprising:

A) fluoride 1,1,2,3-tetrachloropropylene is to prepare 2-chloro-3,3,3 ,-trifluoropropene;

B) by chloro-for 2-3,3,3-trifluoro propene and fluohydric acid gas, with liquid reactive form and combine the hydrogen chloride that feeds intake, react under the existence of liquid-phase fluorination catalyst, 2-chloro-1 is comprised with preparation, the compositions of 1,1,2-tetrafluoropropane, wherein, described hydrogen chloride joins reaction from external source under about 100psig or higher pressure; Then

C) when effectively preparation 2,3,3,3-tetrafluoropropene by described 2-chloro-1,1,1,2-tetrafluoropropane dehydrohalogenation.